Safe maintenance industrial covers

ABSTRACT

The Safety Manhole Industrial Cover (SMIC) is a lightweight temporary safety manhole cover with a hinged access door made with aluminium or a strong nonferrous composite used when sewerage, storm water, water maintenance or inspections are required. It is a temporary self-ventilating design manhole grate to be used whenever the manhole cover is removed when operations are in progress around the manhole. The slots allow for natural light and airflow and it allows workers below ground to see through to the persons above; and vice versa. The safety manhole cover is designed to eliminate the risk of falling from heights regulations requirement whilst works are carried out near or over sewer openings by allowing the operators to walk freely above ground without having a harness to secure themselves.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to AU2014101337, filed Nov. 8, 2014, which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present invention is designed to eliminate the possibility of a fall from heights when working around openings.

BACKGROUND

It is widely known in the industry that opening a manhole is a high risk and fatal activity that requires operators to erect approved safety equipment in order to adhere to current legislation. It is impractical and inefficient to erect and remove, in typical situations, safety barricades each time a manhole is needed to be inspected or maintenance to be carried out.

Manhole covers are heavy, typically circular, plates used to close vertical shafts, i.e. manholes. Manholes provide access to underground areas such as water and storm water pipes, sewage ways and other underground utility areas.

The following is a non-comprehensive list of the procedure to be administered during typical manhole maintenances.

Procedure Prior to Removal of Manhole Cover

Erect safety barricades for a safe working perimeter;

Set up your working equipment around perimeter such as cranes, tripods and certified anchor points;

Have all operators to be anchored to a certified anchor point; and

Use lever to remove the manhole cover.

Procedure Post Inspection or Maintenance

Replace manhole cover;

Remove equipment and detach from certified anchor points; and

Remove safety barricade.

Consequently, it will be realized that the present invention will be a useful alternative to the costly and inefficient operating procedure in the inspection and maintenance of manhole operations as detailed below.

SUMMARY OF INVENTION Technical Problem

When operating around manholes and sewerage openings, barricades are erected to form a barrier so that no outside influences can affect the working environment. All workers below and above ground are to be harnessed to a certified anchor point at all times to prevent falls from heights into the confined space.

Solution to the Problem

A temporary safety manhole cover to be used whenever the common manhole cover is removed or any other water related opening. It is designed to eliminate the need of the existing maintenance procedure of setting up the manhole and being harnessed and anchored to a certified anchor point whilst works are carried out near or over openings. With this innovation, only the operator who is conducting maintenance below ground needs to be secured using a harness hooked up to a winch, which is secured to a certified anchor point situated above ground.

Advantages of the Invention

Eliminating the risk of falling from heights;

Reducing the set up time of the maintenance and/or inspection procedures;

SMIC weighs less than existing manhole covers and can easily be removed and put back in place by a single road worker;

Corrosion resistant;

Cost effective to the cost and maintenance of existing fall from heights safety equipment and certified anchor points;

The cover is versatile and can be made to any shape to suit any application; and

The manhole cover is typically circular in shape but manhole openings of other shapes including but not limited to rectangular and oval configurations.

BRIEF DESCRIPTION OF DRAWINGS

The innovation will be described by example only in reference to the accompanying drawings:

FIG. 1A is a photograph showing the perspective view from the top of an existing circular manhole cover.

FIG. 1B is a photograph showing the perspective view from the underside of an existing circular manhole cover.

FIG. 2 is a diagram showing the perspective view from the top of the circular embodiment of the innovation.

FIG. 3 is a diagram showing the perspective view from the underside of the circular embodiment of the innovation.

FIG. 4 is a diagram showing the isometric view of the circular embodiment of the innovation.

FIG. 5 is a diagram showing the isometric view of the circular embodiment with the opened door depicted of the innovation.

FIG. 6A is a diagram showing the ventilation slot detail of the innovation.

FIG. 6B shows the internal ring, and FIG. 6C shows the stiffening ring.

FIG. 7A is a diagram showing the door rest detail of the circular embodiment of the innovation.

FIG. 7B is a diagram showing the door detail of the circular embodiment of the innovation.

FIG. 8A is a diagram showing the cross section view of the circular embodiment of the innovation.

FIGS. 8B and 8D show the hinge, and and FIGS. 8C and 8E show the hinge pin.

FIG. 9A is a diagram showing the top perspective view of the square embodiment of the innovation, and FIG. 9B shows a side view.

FIG. 10 is a diagram showing the underside perspective view of the square embodiment of the innovation.

FIG. 11 is a diagram showing the isometric view of the square embodiment of the innovation.

FIG. 12A is a diagram showing the isometric view of the square embodiment with the opened door depicted of the innovation. FIGS. 12B and 12C show additional views of this embodiment.

FIG. 13A is a diagram showing the door rest detail of the square embodiment of the innovation.

FIG. 13B is a diagram showing the door detail of the square embodiment of the innovation.

FIG. 14 shows the door stop.

DESCRIPTION OF EMBODIMENTS

Any embodiment of the present invention is meant to be illustrative only and is not meant to be limiting the invention. It is to be understood that throughout the specification that the term “cover” and “grate”; “invention” and “innovation”, will be used interchangeably.

FIG. 2 shows the topside of the temporary manhole cover according to the circular embodiment of the present invention. The manhole cover (1) consists of a flat ventilated plate with a semicircular hinged aperture (2) formed there through.

It is preferable that the circular embodiment and temporary manhole grate (FIG. 1a ) be formed of a lightweight material such as aluminium or even in some circumstances a suitably strong plastic or non-ferrous composite material.

Where the temporary manhole cover will be used in a situation where operators may walk over it then it may be necessary to stiffen the plate by forming the plate with stiffening ribs (3) on the underside (FIG. 3) of the temporary cover. (FIG. 3) shows where a number of stiffening members are welded to the underside of the temporary grate. The ventilation slot detail to be laser cut.

The top plate (1) is laser cut to drawing specifications and ventilation slots (4) are laser cut or via computer numeric control process. This can be 6 realised in other shapes and embodiments of the current invention. In the alternative, when a strong plastic or non-ferrous composite is available, the use of 3D plastic injection molding may be used. The company logo will also be laser cut on the topside of the temporary manhole grate positioned as depicted (5).

A semi-concentric doorstop (6) of the same material is welded to the topside to prevent the door from falling through. The doorstop and the invention is tested to industry weight load bearing specifications.

In the preferred embodiment or any other embodiment of the temporary manhole grate, it will be covered with a textured powder coating with a sand finish to give a non-slip texture.

Since the temporary manhole grate weighs less than 20 kg, it can be readily lifted into place by a single operator.

The stiffening ring (7) is rolled into shape, which is welded to the top plate (8) and is positioned concentric therewith in accordance with the internal ring (9). In the circular embodiment of the invention a stiffening member is welded to the stiffening ring through the diameter on the underside of the top plate (10). In the square embodiment of the invention, the stiffening member (11) is welded to the stiffening ring through the centre.

It should be realised in other embodiments that the top plate, the stiffening member, the stiffening ring, hinge and other features will be cast as a single unitary piece.

The door (12) will be aligned with the doorstop (13), a hinge (14) will be welded together with a hinge pin (15) inserted to secure the door. The door will have a finger hole to allow for operators to lift open the door (17). Accordingly there will be an indent in the doorstop to accommodate for the finger hole (18).

FIG. 5 is an open detail view of the invention. When the door (16) is opened, equipment can be safely passed through to the operator working in the confined space. This is convenient, as it is not required to remove the entire manhole cover in order to pass equipment, which will compromise the safety of all operators working in and around the manhole.

It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect.

Therefore, it should be appreciated that various other changes and modifications can be made to any embodiment described without departing from the spirit and scope of the invention.

VARIATIONS

As the SMIC can come in different shapes and sizes, it can also allow for different materials such as non-metallic materials including but not limited to strong plastics and composites. The utilisation of these materials include but not limited to the following advantages:

Resistance to a wide range of chemical agents including acid rain and salt spray, conditions under which metal parts would suffer. This results in much reduced maintenance and repair costs;

Low weight—with substantial savings in weight over similar metal parts (25%

the weight of steel, 30% lighter than aluminium);

Thermal properties—composite structures act as very good insulators, whilst retaining their shape while not becoming brittle in cold temperatures;

Strength—comparable to aluminium and steel, strength characteristics of many materials;

Safety—fibre-reinforced composites are low in electrical conductivity and are efficient fire retardants; and

Reduced cost—effective techniques have been developed which produce a post-mold paint-finish type surface which requires no further processing, thus eliminating the need for time consuming and expensive finishing.

INDUSTRIAL APPLICABILITY

A Form 15—Compliance Certificate for building Design or Specification is attached detailing the structural design certification of the invention in accordance with the Building Act 1975 (Qld).

The Safety Manhole Industrial Cover (or Safe Maintenance Industrial Cover) (SMIC) is a lightweight temporary safety manhole cover with a hinged access door made with aluminium or a strong nonferrous composite used when sewerage, storm water, water maintenance or inspections are required. It is a temporary self-ventilating design manhole grate to be used whenever the manhole cover is removed when operations are in progress around the manhole. The slots allows for natural light and airflow and it allows workers below ground to see through to the persons above; and vice versa.

The safety manhole cover is designed to eliminate the risk of falling from heights regulations requirement whilst works are carried out near or over sewer openings by allowing the operators to walk freely above ground without having a harness to secure themselves.

The safety manhole cover prevents large objects from falling into the confined space as the cover has been designed to exceed industrial safe load bearing weight standards. The safety manhole cover also has a unique cut out slot design that allows for persons to move freely when cables are in use. In the alternative, the safety manhole cover is embodied in a square form, and other shapes to suit any applications that may be required. 

We claim:
 1. A lightweight temporary safety manhole cover comprising: (i) a plurality of ventilation slots in main body of the cover; (ii) an underside bearing flat stiffening bars; (iii) a load bearing hinged access door; and (iv) the cover sits on top of a concrete lip of the manhole opening wherein the slots occupy a substantial portion of the cover to provide adequate ventilation and light to a worker undertaking maintenance below ground; and at least one of the slots is substantially rectangular in shape and this slot is continuous from centre to circumference of the cover, wherein the manhole cover is substantially circular, spherical, or oval.
 2. The cover according to claim 1 wherein the underside of the safety cover has three flat bars attached to a concentric flat bar ring for support.
 3. The cover according to any one of the claim 2 when used for conducting maintenance below ground enabling a worker to be secured by means of a harness to be lowered down the cover.
 4. The cover according to claim 3 wherein the harness is secured by a cable which is positioned in the slot which is continuous from the centre to the circumference of the cover as defined in claim
 1. 5. A lightweight temporary safety manhole cover comprising: (i) a plurality of ventilation slots in main body of the cover; (ii) an underside bearing flat stiffening bars; (iii) a load bearing hinged access door; and (iv) the cover sits on top of a concrete lip of the manhole opening wherein the slots occupy a substantial portion of the cover to provide adequate ventilation and light to a worker undertaking maintenance below ground; and at least one of the slots is substantially rectangular in shape and this slot is continuous from centre to perimeter of the cover, wherein the manhole cover is substantially rectangular or square.
 6. The cover according to claim 5 wherein the underside of the safety cover has three flat bars attached to a concentric flat bar ring for support.
 7. The cover according to claim 6 when used for conducting maintenance below ground enabling a worker to be secured by means of a harness to be lowered down the cover.
 8. The cover according to claim 7 wherein the harness is secured by a cable which is positioned in the slot which is continuous from the centre to the perimeter of the cover as defined in claim
 5. 